Cushion



P. WEEBER March 20, 1945.

CUSHION Filed Aug.

Paul, 11/6656) atenfed Mar. 20, 1945 UNITED STATES PATENT OFFICE Thisinvention relates to cushions, pads, mats,

I and the like, and among other objects aims to provide an article ofthis character having improved resiliency and other desirable qualities.

The nature of the invention may be readily understood by reference toone illustrative cushion embodying the invention and shown in theaccompanying drawing.

In said drawing: M

Fig. 1 is a perspective view of a portion of a cushion.

Fig. 2 is a fragmentary elevation illustrating the assembly of a cushionand showing'a different construction. i

Fig. 3 is a stress diagram on a larger scale illustrating the operationof th cushion in use.

The invention may advantageously be illustrated as embodied in a spongerubber seat cushion. Within practical limits of economical use of spongerubber" it has not been possible heretofore to produce cushions whichare comfortable for persons of all weights. A cushion com fortable foralight weight person would crush down for a heavy person. On the otherhand, if the cushion be satisfactory for a heavy person it will beuncomfortably hard for a light weight person. Coring out of the cushionto provide A portion of the force applied to the upper face of thecushion in the region of the upper tier ofch'annels II is transmitteddownwardly through the cushion along diagonal lines directed toward thechannels in a lower tier. This is illustrated diagrammatically in Figure3. Such diagonal forces have a horizontal component which appliestension to the material I4 lying between adjacent channels ID in thelower tier I 3. In effect the upper and lower tiers of staggeredchannels create a structure comprising a series of triangular trussesindicated by dotted lines l5, Fig.3. The vertical component of theaforesaid diagonal forces tends also to bend or flex the diagonalelements I8 of the truss. Thus, in resisting forces applied to the uppersurface of the cushion, the ordinary compressive resili- I ence of thematerial is supplemented by its reventilating or cooling channels (whenthe article is used as a seat cushion or the like) increases thesoftness of the cushion and affords a means by which the desiredsoftness may be attained. However, heretofore cushions of this characterwere not uniformly soft or resilient. Some regions are harder thanothers, and after a time the hard regions are perceptible and becomeuncomfortable. All of these objections might be eliminated by the use ofa very deepcushion, but

such a cushion would be prohibitively expensive andotherwiseimpractical.

In the illustrative cushion-the proper degree of cushioning for personsof different weights is attained without development of objectionableharder and softer regions. 'To prevent undue softness in the regionwhere the cushion is cored out, a truss-like structure is developedwhich employs elastic properties in the'material not heretoforeutilized. The illustrative cushion is provided with a series oflongitudinal cores or channels III of elliptical section arranged instaggered relation. In the present instance the cushion is providedwithtwo tiers H and I3 of cores, but additional tiers may be used ifnecessary. These cores or channels may advantageously be formed bycoring the mold in which the material is cast. 1

silience in tension and its resilience in bending. A corollary reactionoccurs in the material I! lying between each of the channels in theupper tier, such material being placed in compression. The ellipticalcontour of the top of each of the channels l0 substantially improves theuniformity of deflection over the entire area of the a cushion, ascompared with channels of other section.

By utilizing the resilience of the material in tension and bending aswell as in compression, excessively soft regions opposite the channelsare substantially eliminated. Similarly, the regions between thechannels are not relatively harder since they have additional stressesimposed thereon. It is possible with the use of sponge rubber with thearrangement of channels above described to approach the softness of themuch .moreexpensive so called foam rubber without crushing down under aperson's weight to the point of being uncomfortable. The resilience ofthe pad may be adjusted for different weights to be cushioned by varyingthe size'and spacing of the staggered passages.

Communicating with the channels 7 II) are transverse passages l8 whichcooperate toventilate and cool the cushion. To prevent complete closing.of the longitudinal channels, auxiliary grooves I9 may be formed in thechannels. These remain open and allow ventilation even though thecompression of the cushion be such as to close the main channel at oneor more points. The grooves I 9, located as they are adjacent theregions of greater rubber thickness,

tend to soften the rubber in these regions, thereby contributing togreater uniformity of defiection.

\ be cushioned.

To facilitate the formation and assembly, the cushion may advantageouslybe molded in two parts 20 and 2|, being divided along the dotted line22. This method of manufacture simplifies removal of the mold coreswhich form the channels I and passages l8. Additional variation in theresilience of the cushion may be obtained by forming sections ofdifferent textures of sponge rubber, one being softer than the other.Cushions may be made with two soft sections, two harder sections, or'one soft and one harder section. In the latter case the cushioningaction is somewhat different when the soft section is uppermost fromthat when a harder section is uppermost; a light weight person will usethe cushion with the softer section uppermost since it will permitgreater local deflection under the lighter weight, thereby contributingto greater comfort.

. In this connection it should be understood that comfortable cushioninginvolves factors not encountered with static loads or uniform weightdistribution. A person's weight is constantly shifting, the distributionof weight is not uniform,

and lack of uniform softness (i; e. lack ofuniformity of deflection ofthe cushion) eventually causes discomfort. It is important therefore.that the cushion be designed to deflect.substantially under a givenweight without, however,

deflecting so far as to crush down and thereby substantially loose itscushioning resilience at any point. Heretofore these characteristicshave been possible only in very deep and prohibitively expensivecushions.

Upon assembly, the upper and lower sections 20 and 2! maybe cementedtogether along their contacting surfaces. Interlocking tongues andgrooves 23 and 24 may be formed at various points on the engagingsurfaces of the respective upper and lower sections to locate thesections in proper register relative to each other.

It is desirable in practice to fabricate pads with. .a series ofdifferent sized cores or channels l0. These, together with sections ofdifierent sponge rubber textures make possible the selection of cushionof the proper softness for the weight to be cushioned.

The foregoing features may be embodied in cushions, mats, and pads forvarious uses. For th ordinary seat cushion the assembled sections inunstressed condition should be about 1 /2 inches thick. For deeper matsand pads an additional tier of channels Ill staggered relative to thoseof the adjacent tier may be employed. For cushioning heavier pressures,less soft, material than the sponge rubber for seat cushions .may beemployed and the channels and passage appropriately adjusted to thecharacter of the load to Obviously the invention is not limited to thedetails of the illustrative cushion since these may be variouslymodified. Furthermore, it is not indispensable that all features of theinvention be used conjolntly since various features may be used toadvantage in different combinations and subcombinations.

Having described my invention, I claim:

1. A seat cushion or the like comprising in combination a pad ofresilient cellular rubber or like material, said pad having extendingtherethrough a series of rows of channels of substantial size, thechannels in-each row staggered with respect to those ,of the adjacentrow, said cushion being subdivided longitudinally into halves alongdiagonal lines connecting adjacent staggered channels so thata cushionhaving different rubber textures in the respective halves may beassembled, and means for connecting said halves together.

2. A seat cushion or the like comprising in combination a pad of spongerubber of limited thickness, said pad havingtherein a plurality of tiersof longitudinally extending parallel channels of substantial section,the channels in one tier being staggered with respect tothose of theadjacent channel so that no portion of a channel of one tier is directlyabove any portion of a channel of an adjacent tier, said cushion beingsubdivided longitudinally into halves along diagonal lines extendingfrom channels in one tier to adjacent channels in another tier whereby acomposite cushion may be assembled from halves made of sponge rubbertextures of a softness appropriate to cushion the load to be imposedthereon.

3. A seat cushion or the like comprising in combination a pad of spongerubber of limited thickness, said pad having therein a plurality oftiers of longitudinally extending parallel channels of substantialsection, the channels in one tier being staggered with respect to thoseof the adj acent channel so that no portion of a channel of one tier isdirectly above any portion of a channel of an adjacent tier, andauxiliary grooves of relatively small size in the channel walls tomaintain longitudinal ventilating passages in the event said channels beclosed by the load imposed onthe cushion.

4. A seat cushion or the like comprising in combination a pad of spongerubber of limited thickness, said pad having therein a plurality oftiers of longitudinally extending parallel channels of substantialsection, the channels in one tier being staggered with respect to thoseof the adjacent channel so that no portion of a channel of one tier isdirectly above any portion of a channel of an adjacenttier, said cushionalso having a plurality of ventilating passages extending from eachchannel to the surface of the cushion, and auxiliary grooves ofrelatively small size closed by the load imposed on the cushion.

PAUL WEEBER.

